Patent GB-191421088-A (GB)
Title: Improvements in Automatic Safety Apparatus for Railways.
IPC: B61L3/04
Filed: 1914-10-16
Granted: 1915-10-18
Abstract: 21,088. Barnes Train Stop Co., and Barnes, F. G. Oct. 16. Track apparatus actuating signals on trains and for stopping trains; recording signals.-The driver's brake valve is operated by a compressedair cylinder when an exhaust valve on the train is opened by a track contact-arm, and a record is made on a clock-driven disk when the brake valve is thus operated and also when the brakes are released by resetting the apparatus. The track contacts are resilient and have soft faces which are adapted to receive an impression of marks identifying the locomotive which strikes it. The train apparatus is arranged so as to bring alternative contact-arms into operation for different directions of travel of the rocomotive. The track contacts for a given direction of traffic are placed on the left of the centre line of the track. Fig. 11 shows a track contact comprising a pivoted bell-crank 16 with a spring-like upstanding arm and an arm with a counterweight 17, which moves between limits fixed by a quadrant 18. The spring arm carries a solid top with soft-metal faces 14. Co-axial with the bell-crank is a sheave 10 with a counterweight 11 and a projection 20 thereon, which engages the bell-crank to lower the arm when a rope or other connexion 23 to the signal or to the cabin is pulled. The whole device is carried on an angle-iron 5, which is clamped to the track rail 7. Two contact-arms 2, 3 are pivoted on a vertical spindle 26 beneath the locomotive so as to project laterally, and cams 29, 30 rigid with the arms are arranged to engage and rock a vertically-hanging toothed pawl 57 when that arm which is on the left-hand side of the track, looking in the direction of travel of the train, engages a raised track contact. The arms are held in their normal position by spring jaws 31 and are returned at once after operation to this position by other springs. The pawl 57 raises the spindle of the exhaust valve 53 and so puts the lower end of cylinder 48, Figs. 17 and 20, to atmosphere through the pipe 70, valve 53, and a whistle 73 connected to the port 71. The pawl 57 is held up by the spring- pressed pawl 58 engaging the ratchet teeth on the pawl until the driver operates a resetting- cock 134 to supply compressed air through the pipe 136 to the cylinder 61, the piston of which rocks the pawl 58. The arm 2, 3 which is on the right side of the track is removed from operative position by arms 41, 42 carried on rings 39, 40 which are rotated by links 43, 44, Fig. 4, and a cross-head 169, which is moved in one direction or the other along a guide 171 by a link 91 connected to a member 89 driven by a friction clutch on a bogie axle 76. The position of the cross-head, and consequently of the arms 2, 3, thus depends upon the direction of rotation of the axle 76. The upper end of the cylinder 48 is connected through the port 123 to a pressure reservoir, and the lower end communicates therewith through a restricted channel 130. Normally, the air pressure on both sides of the piston being equal, the piston is raised. When the valve 53 is opened, the piston is forced downwards and, through a bellcrank 111, rotates a sleeve 103 and the attached arm 105, which engages the handle 99 of the driver's brake valve 98, which is thereby moved to apply the brakes. The times of actuation of the exhaust valve by a track contact and its release by the driver are recorded by pneumatically-operated styles 154, 155 respectively. The cylinder 153 is connected to the exhaust conduit 72, and its piston is pushed forward when the exhaust valve is actuated and rocks the sleeve 150 carrying the style 154, which is moved into contact with a metallic paper disk carried by a clock-driven plate 142. The cylinder 146 which actuates the style 155 is supplied with compressed air when the three-way resetting-cock 134 is actuated to connect the releasing-cylinder 61 for the exhaust valve to the air reservoir. In a modified construction of recording-apparatus, the styles are normally in contact with the recording-disk and are moved so as to produce deviations from the circular line when air is passed to the operating-cylinders